Skip to main content

Aptitude Day 76


Ratio and Proportion:

 1. If 4x2+9y2 = 12xy, then x:y is:

Solution:
             4x2-12xy+9y2 = 0
             4x2-6xy-6xy+9y2 = 0
             (2x-3y)2 = 0
             2x=3y
             x/y = 3/2.

             The ratio is 3:2.

2. If 9x2-16xy+7y2 = 0, then x:y is:

Solution:
              9x2-16xy+7y2 = 0
              9x2-9xy-7xy+7y2 = 0
              (x-y)(9x-7y) = 0
               x=y, 9x=7y

               x:y = (1:1) or (7:9)

Comments

Post a Comment

Popular posts from this blog

Aptitude Day 47

Problem On Numbers 1. Three numbers are in the ratio 1:2:3 and their average is 180. What's the largest number? Solution:                 Let the numbers be x, 2x and 3x.                 x+2x+3x = 180                          6x = 180                            x = 30                The largest number is 3x = 90. Problem to solve: Three numbers are in the ratio of 4:2:3 and their product is 648. Find the smallest number. 
Post a Comment
Read more

Vocabulary Day 21

Stammer Thesaurus: Verb : stutter in speech, speak haltingly, speech defect           halt, hesitate, pause, stop, sputter... Antonyms : say quickly, pronounce, enunciate... Example sentences: ·          He was stammering when the teacher caught him red-handed. ·          One should avoid the stammering while delivering a speech. 
Post a Comment
Read more